bstaats · September 28, 2011 23:19 · johan · Oct 23, 2011
diff --git a/index.html b/index.html
 <!DOCTYPE html>
 <html>
  <head>
    <meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
    <title>Force Layouts - Multiple Foci Collision</title>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.js"></script>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.geom.js"></script>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.layout.js"></script>
    <style type="text/css">

 rect{
  fill: white;
 }

 circle {
  stroke: #000;
  stroke-opacity: .5;
 }

    </style>
  </head>
  <body>
    <div id="body">
      <div id="chart"></div>
    </div>
    <script type="text/javascript">

 var w = 960,
    h = 500;

 var nodes = d3.range(5).map(function(i) {
  return {type: Math.random() * 5 | 0,
          radius: 30,
          fixed:true,
          type:i,
          x: (i+1) * (w / 6),
          y: h / 2};
    }),
    color = d3.scale.category10();

 var force = d3.layout.force()
    .gravity(0)
    .charge(0)
    .nodes(nodes)
    .size([w, h]);

 force.start();

 var svg = d3.select("#chart").append("svg:svg")
    .attr("width", w)
    .attr("height", h);

 svg.append("svg:rect")
    .attr("width", w)
    .attr("height", h);

 svg.selectAll("circle")
    .data(nodes)
  .enter().append("svg:circle")
    .attr("r", function(d) { return d.radius - 2; })
    .style("fill", function(d, i) { return color(d.type); });

 force.on("tick", function(e) {
  var q = d3.geom.quadtree(nodes),
      k = e.alpha * .1,
      i = 0,
      n = nodes.length,
      o;

  while (++i < n) {
    o = nodes[i];
    if (o.fixed) continue;
    c = nodes[o.type];
    o.x += (c.x - o.x) * k;
    o.y += (c.y - o.y) * k;
    q.visit(collide(o));
  }

  svg.selectAll("circle")
      .attr("cx", function(d) { return d.x; })
      .attr("cy", function(d) { return d.y; });
 });

 var p0;
 svg.on("mousemove", function() {
  var p1 = d3.svg.mouse(this),
      node = {radius:Math.random() * 12 + 4, type: Math.random() * 5 | 0, x: p1[0], y: p1[1], px: (p0 || (p0 = p1))[0], py: p0[1]};

  p0 = p1;

  svg.append("svg:circle")
      .data([node])
      .attr("cx", function(d) { return d.x; })
      .attr("cy", function(d) { return d.y; })
      .attr("r", function(d) { return d.radius - 2; })
      .style("fill", function(d) {return color(d.type);})
      .transition()
        .delay(3000)
        .attr("r", 1e-6)
        .each("end", function() { nodes.splice(6, 1); })
        .remove();

  nodes.push(node);
  force.resume();
 });

 function collide(node) {
  var r = node.radius + 16,
      nx1 = node.x - r,
      nx2 = node.x + r,
      ny1 = node.y - r,
      ny2 = node.y + r;
  return function(quad, x1, y1, x2, y2) {
    if (quad.point && (quad.point !== node)) {
      var x = node.x - quad.point.x,
          y = node.y - quad.point.y,
          l = Math.sqrt(x * x + y * y),
          r = node.radius + quad.point.radius;
      if (l < r) {
        l = (l - r) / l * .5;
        node.px += x * l;
        node.py += y * l;
      }
    }
    return x1 > nx2
        || x2 < nx1
        || y1 > ny2
        || y2 < ny1;
  };
 }

    </script>
  </body>
 </html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
	<title>Force Layouts - Multiple Foci Collision</title>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.js"></script>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.geom.js"></script>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.layout.js"></script>
	<style type="text/css">

	rect{
	fill: white;
	}

	circle {
	stroke: #000;
	stroke-opacity: .5;
	}

	</style>
	</head>
	<body>
	<div id="body">
	<div id="chart"></div>
	</div>
	<script type="text/javascript">

	var w = 960,
	h = 500;

	var nodes = d3.range(5).map(function(i) {
	return {type: Math.random() * 5 \| 0,
	radius: 30,
	fixed:true,
	type:i,
	x: (i+1) * (w / 6),
	y: h / 2};
	}),
	color = d3.scale.category10();

	var force = d3.layout.force()
	.gravity(0)
	.charge(0)
	.nodes(nodes)
	.size([w, h]);

	force.start();

	var svg = d3.select("#chart").append("svg:svg")
	.attr("width", w)
	.attr("height", h);

	svg.append("svg:rect")
	.attr("width", w)
	.attr("height", h);

	svg.selectAll("circle")
	.data(nodes)
	.enter().append("svg:circle")
	.attr("r", function(d) { return d.radius - 2; })
	.style("fill", function(d, i) { return color(d.type); });

	force.on("tick", function(e) {
	var q = d3.geom.quadtree(nodes),
	k = e.alpha * .1,
	i = 0,
	n = nodes.length,
	o;

	while (++i < n) {
	o = nodes[i];
	if (o.fixed) continue;
	c = nodes[o.type];
	o.x += (c.x - o.x) * k;
	o.y += (c.y - o.y) * k;
	q.visit(collide(o));
	}

	svg.selectAll("circle")
	.attr("cx", function(d) { return d.x; })
	.attr("cy", function(d) { return d.y; });
	});

	var p0;
	svg.on("mousemove", function() {
	var p1 = d3.svg.mouse(this),
	node = {radius:Math.random() * 12 + 4, type: Math.random() * 5 \| 0, x: p1[0], y: p1[1], px: (p0 \|\| (p0 = p1))[0], py: p0[1]};

	p0 = p1;

	svg.append("svg:circle")
	.data([node])
	.attr("cx", function(d) { return d.x; })
	.attr("cy", function(d) { return d.y; })
	.attr("r", function(d) { return d.radius - 2; })
	.style("fill", function(d) {return color(d.type);})
	.transition()
	.delay(3000)
	.attr("r", 1e-6)
	.each("end", function() { nodes.splice(6, 1); })
	.remove();

	nodes.push(node);
	force.resume();
	});

	function collide(node) {
	var r = node.radius + 16,
	nx1 = node.x - r,
	nx2 = node.x + r,
	ny1 = node.y - r,
	ny2 = node.y + r;
	return function(quad, x1, y1, x2, y2) {
	if (quad.point && (quad.point !== node)) {
	var x = node.x - quad.point.x,
	y = node.y - quad.point.y,
	l = Math.sqrt(x * x + y * y),
	r = node.radius + quad.point.radius;
	if (l < r) {
	l = (l - r) / l * .5;
	node.px += x * l;
	node.py += y * l;
	}
	}
	return x1 > nx2
	\|\| x2 < nx1
	\|\| y1 > ny2
	\|\| y2 < ny1;
	};
	}

	</script>
	</body>
	</html>